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1.
EMBO J ; 42(4): e111883, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36546550

RESUMEN

Proper stamen filament elongation is essential for pollination and plant reproduction. Plant hormones are extensively involved in every stage of stamen development; however, the cellular mechanisms by which phytohormone signals couple with microtubule dynamics to control filament elongation remain unclear. Here, we screened a series of Arabidopsis thaliana mutants showing different microtubule defects and revealed that only those unable to sever microtubules, lue1 and ktn80.1234, displayed differential floral organ elongation with less elongated stamen filaments. Prompted by short stamen filaments and severe decrease in KTN1 and KTN80s expression in qui-2 lacking five BZR1-family transcription factors (BFTFs), we investigated the crosstalk between microtubule severing and brassinosteroid (BR) signaling. The BFTFs transcriptionally activate katanin-encoding genes, and the microtubule-severing frequency was severely reduced in qui-2. Taken together, our findings reveal how BRs can regulate cytoskeletal dynamics to coordinate the proper development of reproductive organs.


Asunto(s)
Brasinoesteroides , Katanina , Microtúbulos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Brasinoesteroides/metabolismo , Katanina/genética , Katanina/metabolismo , Microtúbulos/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo
2.
Plant Physiol ; 193(2): 1561-1579, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37467431

RESUMEN

An apical hook is a special structure formed during skotomorphogenesis in dicotyledonous plant species. It is critical for protecting the shoot apical meristem from mechanical damage during seed germination and hypocotyl elongation in soil. Brassinosteroid (BR) and jasmonate (JA) phytohormones antagonistically regulate apical hook formation. However, the interrelationship between BRs and JAs in this process has not been well elucidated. Here, we reveal that JAs repress BRs to regulate apical hook development in Arabidopsis (Arabidopsis thaliana). Exogenous application of methyl jasmonate (MeJA) repressed the expression of the rate-limiting BR biosynthetic gene DWARF4 (DWF4) in a process relying on 3 key JA-dependent transcription factors, MYC2, MYC3, and MYC4. We demonstrated that MYC2 interacts with the critical BR-activated transcription factor BRASSINAZOLE RESISTANT 1 (BZR1), disrupting the association of BZR1 with its partner transcription factors, such as those of the PHYTOCHROME INTERACTING FACTOR (PIF) family and downregulating the expression of their target genes, such as WAVY ROOT GROWTH 2 (WAG2), encoding a protein kinase essential for apical hook development. Our results indicate that JAs not only repress the expression of BR biosynthetic gene DWF4 but, more importantly, attenuate BR signaling by inhibiting the transcriptional activation of BZR1 by MYC2 during apical hook development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Brasinoesteroides/metabolismo , Arabidopsis/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas
3.
BMC Cancer ; 24(1): 418, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580939

RESUMEN

BACKGROUND: This study aimed to develop and validate a machine learning (ML)-based fusion model to preoperatively predict Ki-67 expression levels in patients with head and neck squamous cell carcinoma (HNSCC) using multiparametric magnetic resonance imaging (MRI). METHODS: A total of 351 patients with pathologically proven HNSCC from two medical centers were retrospectively enrolled in the study and divided into training (n = 196), internal validation (n = 84), and external validation (n = 71) cohorts. Radiomics features were extracted from T2-weighted images and contrast-enhanced T1-weighted images and screened. Seven ML classifiers, including k-nearest neighbors (KNN), support vector machine (SVM), logistic regression (LR), random forest (RF), linear discriminant analysis (LDA), naive Bayes (NB), and eXtreme Gradient Boosting (XGBoost) were trained. The best classifier was used to calculate radiomics (Rad)-scores and combine clinical factors to construct a fusion model. Performance was evaluated based on calibration, discrimination, reclassification, and clinical utility. RESULTS: Thirteen features combining multiparametric MRI were finally selected. The SVM classifier showed the best performance, with the highest average area under the curve (AUC) of 0.851 in the validation cohorts. The fusion model incorporating SVM-based Rad-scores with clinical T stage and MR-reported lymph node status achieved encouraging predictive performance in the training (AUC = 0.916), internal validation (AUC = 0.903), and external validation (AUC = 0.885) cohorts. Furthermore, the fusion model showed better clinical benefit and higher classification accuracy than the clinical model. CONCLUSIONS: The ML-based fusion model based on multiparametric MRI exhibited promise for predicting Ki-67 expression levels in HNSCC patients, which might be helpful for prognosis evaluation and clinical decision-making.


Asunto(s)
Neoplasias de Cabeza y Cuello , Imágenes de Resonancia Magnética Multiparamétrica , Humanos , Teorema de Bayes , Antígeno Ki-67/genética , Radiómica , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico por imagen , Aprendizaje Automático , Neoplasias de Cabeza y Cuello/diagnóstico por imagen
4.
FASEB J ; 37(3): e22791, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36723768

RESUMEN

Atherosclerosis (As) is a chronic vascular inflammatory disease. Macrophages are the most important immune cells in atherosclerotic plaques, and the phenotype of plaque macrophages shifts dynamically to adapt to changes in the plaque microenvironment. The aerobic microenvironment of early atherosclerotic plaques promotes the transformation of M2/alternatively activated macrophages mainly through oxidative phosphorylation; the anoxic microenvironment of advanced atherosclerotic plaques mainly promotes the formation of M1/classically activated macrophages through anaerobic glycolysis; and the adventitia angiogenesis of aged atherosclerotic plaques leads to an increase in the proportion of M2/M1 macrophages. Therefore, this review deeply elucidates the dynamic change mechanism of plaque macrophages and the regulation of plaque oxygen content and immune metabolism to find new targets for the treatment of As.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/metabolismo , Oxígeno/metabolismo , Aterosclerosis/metabolismo , Macrófagos/metabolismo , Fenotipo
5.
Exp Cell Res ; 425(1): 113525, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36841324

RESUMEN

Gastric cancer is a serious malignant tumor in the world, accounting for the third cause of cancer death worldwide. The pathogenesis of gastric cancer is very complex, in which epigenetic inheritance plays an important role. In our study, we found that DZIP3 was significantly up-regulated in gastric cancer tissues as compared to adjacent normal tissue, which suggested it may be play a crucial part in gastric cancer. To clarify the mechanism of it, we further analyzed the interacting proteome and transcriptome of DZIP3. An association between DZIP3 and some epigenetic regulators, such as CUL4B complex, was verified. We also present the first proteomic characterization of the protein-protein interaction (PPI) network of DZIP3. Then, the transcriptome analysis of DZIP3 demonstrated that knockdown DZIP3 increased a cohort of genes, including SETD7 and ZBTB4, which have essential role in tumors. We also revealed that DZIP3 promotes proliferation and metastasis of gastric cancer cells. And the higher expression of DZIP3 is positively associated with the poor prognosis of several cancers. In summary, our study revealed a mechanistic role of DZIP3 in promoting proliferation and metastasis in gastric cancer, supporting the pursuit of DZIP3 as a potential target for gastric cancer therapy.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , Proteómica , Proliferación Celular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Metástasis de la Neoplasia , N-Metiltransferasa de Histona-Lisina/genética , Proteínas de Unión al ARN/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Cullin/metabolismo
6.
Hepatobiliary Pancreat Dis Int ; 21(6): 559-568, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35643910

RESUMEN

BACKGROUND: Current surveillance strategies for hepatocellular carcinoma (HCC) among patients with nonalcoholic fatty liver disease (NAFLD) are insufficient. This study aimed to investigate the diagnostic performance of alpha-fetoprotein (AFP), protein induced by vitamin K absence or antagonist-II (PIVKA-II), lens culinaris agglutinin-reactive fraction of AFP (AFP-L3), and their combinations in HCC underlying NAFLD patients. METHODS: Serologic AFP, AFP-L3, and PIVKA-II levels in NAFLD patients with and without HCC were measured. By receiver operating characteristic (ROC) analyses, the area under the curve (AUC), sensitivity, and specificity were obtained to evaluate the diagnostic accuracy of each biomarker and their combinations. RESULTS: This study was conducted on 139 patients with NAFLD-HCC and 345 NAFLD controls. The elevation of these three biomarkers was observed in patients with NAFLD-HCC compared to those in NAFLD controls (all P < 0.001). When they were analyzed individually, PIVKA-II showed the best performance in diagnosing any-stage HCC with an AUC of 0.869, followed by AFP (0.763; vs. PIVKA-II, P < 0.001) and AFP-L3 (0.689; vs. PIVKA-II, P < 0.001). When they were analyzed in combination, AFP + PIVKA-II yielded the highest AUC (0.906), followed by AFP + PIVKA-II + AFP-L3 (0.904; vs. AFP + PIVKA-II, P = 0.086), PIVKA-II + AFP-L3 (0.881; vs. AFP + PIVKA-II, P < 0.001), and AFP + AFP-L3 (0.759; vs. AFP + PIVKA-II, P < 0.001). Similar findings were obtained in the subgroup with early-stage NAFLD-HCC, as well as the non-cirrhotic subgroup. CONCLUSIONS: These data validated the better diagnostic ability of PIVKA-II than AFP or AFP-L3 alone for diagnosing any-stage HCC among patients with NAFLD, and the combination of AFP + PIVKA-II significantly improved the diagnostic accuracy of NAFLD-HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Humanos , alfa-Fetoproteínas/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Neoplasias Hepáticas/diagnóstico , Protrombina/análisis , Protrombina/metabolismo , Precursores de Proteínas , Biomarcadores , Vitamina K , Biomarcadores de Tumor
7.
J Integr Plant Biol ; 64(8): 1502-1513, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35587568

RESUMEN

Receptor-like kinases (RLKs) play key roles in regulating various physiological aspects in plant growth and development. In Arabidopsis thaliana, there are at least 223 leucine-rich repeat (LRR) RLKs. The functions of the majority of RLKs in the LRR XI subfamily were previously revealed. Only three RLKs were not characterized. Here we report that two independent triple mutants of these RLKs, named ROOT ELONGATION RECEPTOR KINASES (REKs), exhibit increased cell numbers in the root apical meristem and enhanced cell size in the elongation and maturation zones. The promoter activities of a number of Quiescent Center marker genes are significantly up-regulated in the triple mutant. However, the promoter activities of several marker genes known to control root stem cell niche activities are not altered. RNA-seq analysis revealed that a number of cell wall remodeling genes are significantly up-regulated in the triple mutant. Our results suggest that these REKs play key roles in regulating root development likely via negatively regulating the expression of a number of key cell wall remodeling genes.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Pared Celular/metabolismo , Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Raíces de Plantas/metabolismo , Proteínas Serina-Treonina Quinasas
8.
Eur Radiol ; 31(10): 7500-7511, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33860832

RESUMEN

OBJECTIVES: To develop and validate a pre-transcatheter arterial chemoembolization (TACE) MRI-based radiomics model for predicting tumor response in intermediate-advanced hepatocellular carcinoma (HCC) patients. MATERIALS: Ninety-nine intermediate-advanced HCC patients (69 for training, 30 for validation) treated with TACE were enrolled. MRI examinations were performed before TACE, and the efficacy was evaluated according to the mRECIST criterion 3 months after TACE. A total of 396 radiomics features were extracted from T2-weighted pre-TACE images, and least absolute shrinkage and selection operator (LASSO) regression was applied to feature selection and model construction. The performance of the model was evaluated by receiver operating characteristic (ROC) curves, calibration curves, and decision curves. RESULTS: The AFP value, Child-Pugh score, and BCLC stage showed a significant difference between the TACE response (TR) and non-TACE response (nTR) patients. Six radiomics features were selected by LASSO and the radiomics score (Rad-score) was calculated as the sum of each feature multiplied by the non-zero coefficient from LASSO. The AUCs of the ROC curve based on Rad-score were 0.812 and 0.866 in the training and validation cohorts, respectively. To improve the diagnostic efficiency, the Rad-score was further integrated with the above clinical indicators to form a novel predictive nomogram. Results suggested that the AUC increased to 0.861 and 0.884 in the training and validation cohorts, respectively. Decision curve analysis showed that the radiomics nomogram was clinically useful. CONCLUSION: The radiomics and clinical indicator-based predictive nomogram can well predict TR in intermediate-advanced HCC and can further be applied for auxiliary diagnosis of clinical prognosis. KEY POINTS: • The therapeutic outcome of TACE varies greatly even for patients with the same clinicopathologic features. • Radiomics showed excellent performance in predicting the TACE response. • Decision curves demonstrated that the novel predictive model based on the radiomics signature and clinical indicators has great clinical utility.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/terapia , Imagen por Resonancia Magnética , Nomogramas , Estudios Retrospectivos
9.
Nano Lett ; 17(1): 143-149, 2017 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-28073262

RESUMEN

The characterization of the aggregation kinetics of protein amyloids and the structural properties of the ensuing aggregates are vital in the study of the pathogenesis of many neurodegenerative diseases and the discovery of therapeutic targets. In this article, we show that the fluorescence lifetime of synthetic dyes covalently attached to amyloid proteins informs on the structural properties of amyloid clusters formed both in vitro and in cells. We demonstrate that the mechanism behind such a "lifetime sensor" of protein aggregation is based on fluorescence self-quenching and that it offers a good dynamic range to report on various stages of aggregation without significantly perturbing the process under investigation. We show that the sensor informs on the structural density of amyloid clusters in a high-throughput and quantitative manner and in these aspects the sensor outperforms super-resolution imaging techniques. We demonstrate the power and speed of the method, offering capabilities, for example, in therapeutic screenings that monitor biological self-assembly. We investigate the mechanism and advantages of the lifetime sensor in studies of the K18 protein fragment of the Alzheimer's disease related protein tau and its amyloid aggregates formed in vitro. Finally, we demonstrate the sensor in the study of aggregates of polyglutamine protein, a model used in studies related to Huntington's disease, by performing correlative fluorescence lifetime imaging microscopy and structured-illumination microscopy experiments in cells.


Asunto(s)
Amiloide/química , Amiloide/metabolismo , Agregado de Proteínas , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Fluorescencia , Colorantes Fluorescentes/química , Células HEK293 , Humanos , Enfermedad de Huntington/diagnóstico por imagen , Enfermedad de Huntington/metabolismo , Cinética , Imagen Óptica , Péptidos/química , Péptidos/metabolismo , Conformación Proteica
10.
BMC Biol ; 13: 2, 2015 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-25575667

RESUMEN

BACKGROUND: Endoplasmic reticulum (ER) lumenal protein thiol redox balance resists dramatic variation in unfolded protein load imposed by diverse physiological challenges including compromise in the key upstream oxidases. Lumenal calcium depletion, incurred during normal cell signaling, stands out as a notable exception to this resilience, promoting a rapid and reversible shift towards a more reducing poise. Calcium depletion induced ER redox alterations are relevant to physiological conditions associated with calcium signaling, such as the response of pancreatic cells to secretagogues and neuronal activity. The core components of the ER redox machinery are well characterized; however, the molecular basis for the calcium-depletion induced shift in redox balance is presently obscure. RESULTS: In vitro, the core machinery for generating disulfides, consisting of ERO1 and the oxidizing protein disulfide isomerase, PDI1A, was indifferent to variation in calcium concentration within the physiological range. However, ER calcium depletion in vivo led to a selective 2.5-fold decline in PDI1A mobility, whereas the mobility of the reducing PDI family member, ERdj5 was unaffected. In vivo, fluorescence resonance energy transfer measurements revealed that declining PDI1A mobility correlated with formation of a complex with the abundant ER chaperone calreticulin, whose mobility was also inhibited by calcium depletion and the calcium depletion-mediated reductive shift was attenuated in cells lacking calreticulin. Measurements with purified proteins confirmed that the PDI1A-calreticulin complex dissociated as Ca(2+) concentrations approached those normally found in the ER lumen ([Ca(2+)]K(0.5max) = 190 µM). CONCLUSIONS: Our findings suggest that selective sequestration of PDI1A in a calcium depletion-mediated complex with the abundant chaperone calreticulin attenuates the effective concentration of this major lumenal thiol oxidant, providing a plausible and simple mechanism for the observed shift in ER lumenal redox poise upon physiological calcium depletion.


Asunto(s)
Calcio/deficiencia , Difusión , Retículo Endoplásmico/metabolismo , Proteína Disulfuro Isomerasas/metabolismo , Animales , Células COS , Calcio/metabolismo , Calreticulina/metabolismo , Chlorocebus aethiops , Disulfuros/metabolismo , Células HEK293 , Proteínas del Choque Térmico HSP40/metabolismo , Humanos , Ratones , Chaperonas Moleculares/metabolismo , Oxidación-Reducción , Unión Proteica
11.
Biophys J ; 108(5): 999-1002, 2015 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-25762312

RESUMEN

FRET is widely used for the study of protein-protein interactions in biological samples. However, it is difficult to quantify both the FRET efficiency (E) and the affinity (Kd) of the molecular interaction from intermolecular FRET signals in samples of unknown stoichiometry. Here, we present a method for the simultaneous quantification of the complete set of interaction parameters, including fractions of bound donors and acceptors, local protein concentrations, and dissociation constants, in each image pixel. The method makes use of fluorescence lifetime information from both donor and acceptor molecules and takes advantage of the linear properties of the phasor plot approach. We demonstrate the capability of our method in vitro in a microfluidic device and also in cells, via the determination of the binding affinity between tagged versions of glutathione and glutathione S-transferase, and via the determination of competitor concentration. The potential of the method is explored with simulations.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia/métodos , Microfluídica/métodos , Células HEK293 , Humanos , Proteínas Luminiscentes/metabolismo
12.
Br J Radiol ; 97(1154): 439-450, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308028

RESUMEN

OBJECTIVES: Accurate axillary evaluation plays an important role in prognosis and treatment planning for breast cancer. This study aimed to develop and validate a dynamic contrast-enhanced (DCE)-MRI-based radiomics model for preoperative evaluation of axillary lymph node (ALN) status in early-stage breast cancer. METHODS: A total of 410 patients with pathologically confirmed early-stage invasive breast cancer (training cohort, N = 286; validation cohort, N = 124) from June 2018 to August 2022 were retrospectively recruited. Radiomics features were derived from the second phase of DCE-MRI images for each patient. ALN status-related features were obtained, and a radiomics signature was constructed using SelectKBest and least absolute shrinkage and selection operator regression. Logistic regression was applied to build a combined model and corresponding nomogram incorporating the radiomics score (Rad-score) with clinical predictors. The predictive performance of the nomogram was evaluated using receiver operator characteristic (ROC) curve analysis and calibration curves. RESULTS: Fourteen radiomic features were selected to construct the radiomics signature. The Rad-score, MRI-reported ALN status, BI-RADS category, and tumour size were independent predictors of ALN status and were incorporated into the combined model. The nomogram showed good calibration and favourable performance for discriminating metastatic ALNs (N + (≥1)) from non-metastatic ALNs (N0) and metastatic ALNs with heavy burden (N + (≥3)) from low burden (N + (1-2)), with the area under the ROC curve values of 0.877 and 0.879 in the training cohort and 0.859 and 0.881 in the validation cohort, respectively. CONCLUSIONS: The DCE-MRI-based radiomics nomogram could serve as a potential non-invasive technique for accurate preoperative evaluation of ALN burden, thereby assisting physicians in the personalized axillary treatment for early-stage breast cancer patients. ADVANCES IN KNOWLEDGE: This study developed a potential surrogate of preoperative accurate evaluation of ALN status, which is non-invasive and easy-to-use.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Estudios Retrospectivos , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Estudios de Factibilidad , Radiómica , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Nomogramas , Imagen por Resonancia Magnética/métodos
13.
Acad Radiol ; 31(1): 142-156, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37280128

RESUMEN

RATIONALE AND OBJECTIVES: This study aimed to develop and validate a dual-energy CT (DECT)-based model for preoperative prediction of the number of central lymph node metastases (CLNMs) in clinically node-negative (cN0) papillary thyroid carcinoma (PTC) patients. MATERIALS AND METHODS: Between January 2016 and January 2021, 490 patients who underwent lobectomy or thyroidectomy, CLN dissection, and preoperative DECT examinations were enrolled and randomly allocated into the training (N = 345) and validation cohorts (N = 145). The patients' clinical characteristics and quantitative DECT parameters obtained on primary tumors were collected. Independent predictors of> 5 CLNMs were identified and integrated to construct a DECT-based prediction model, for which the area under the curve (AUC), calibration, and clinical usefulness were assessed. Risk group stratification was performed to distinguish patients with different recurrence risks. RESULTS: More than 5 CLNMs were found in 75 (15.3%) cN0 PTC patients. Age, tumor size, normalized iodine concentration (NIC), normalized effective atomic number (nZeff) and the slope of the spectral Hounsfield unit curve (λHu) in the arterial phase were independently associated with> 5 CLNMs. The DECT-based nomogram that incorporated predictors demonstrated favorable performance in both cohorts (AUC: 0.842 and 0.848) and significantly outperformed the clinical model (AUC: 0.688 and 0.694). The nomogram showed good calibration and added clinical benefit for predicting> 5 CLNMs. The KaplanMeier curves for recurrence-free survival showed that the high- and low-risk groups stratified by the nomogram were significantly different. CONCLUSION: The nomogram based on DECT parameters and clinical factors could facilitate preoperative prediction of the number of CLNMs in cN0 PTC patients.


Asunto(s)
Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/diagnóstico por imagen , Cáncer Papilar Tiroideo/cirugía , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Tiroidectomía , Nomogramas , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Ganglios Linfáticos/patología
14.
Acad Radiol ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38490840

RESUMEN

RATIONALE AND OBJECTIVES: This study aimed to construct a machine learning radiomics-based model using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) images to evaluate non-sentinel lymph node (NSLN) metastasis in Chinese breast cancer (BC) patients who underwent total mastectomy (TM) and had 1-2 positive sentinel lymph nodes (SLNs). MATERIALS AND METHODS: In total, 494 patients were retrospectively enrolled from two hospitals, and were divided into the training (n = 286), internal validation (n = 122), and external validation (n = 86) cohorts. Features were extracted from DCE-MRI images for each patient and screened. Six ML classifies were trained and the best classifier was evaluated to calculate radiomics (Rad)-scores. A combined model was developed based on Rad-scores and clinical risk factors, then the calibration, discrimination, reclassification, and clinical usefulness were evaluated. RESULTS: 14 radiomics features were ultimately selected. The random forest (RF) classifier showed the best performance, with the highest average area under the curve (AUC) of 0.833 in the validation cohorts. The combined model incorporating RF-based Rad-scores, tumor size, lymphovascular invasion, and proportion of positive SLNs resulted in the best discrimination ability, with AUCs of 0.903, 0.890, and 0.836 in the training, internal validation, and external validation cohorts, respectively. Furthermore, the combined model significantly improved the classification accuracy and clinical benefit for NSLN metastasis prediction. CONCLUSION: A RF-based combined model using DCE-MRI images exhibited a promising performance for predicting NSLN metastasis in Chinese BC patients who underwent TM and had 1-2 positive SLNs, thereby aiding in individualized clinical treatment decisions.

15.
Front Plant Sci ; 15: 1347842, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38328701

RESUMEN

FHY3 and its homologous protein FAR1 are the founding members of FRS family. They exhibited diverse and powerful physiological functions during evolution, and participated in the response to multiple abiotic stresses. FRF genes are considered to be truncated FRS family proteins. They competed with FRS for DNA binding sites to regulate gene expression. However, only few studies are available on FRF genes in plants participating in the regulation of abiotic stress. With wide adaptability and high stress-resistance, barley is an excellent candidate for the identification of stress-resistance-related genes. In this study, 22 HvFRFs were detected in barley using bioinformatic analysis from whole genome. According to evolution and conserved motif analysis, the 22 HvFRFs could be divided into subfamilies I and II. Most promoters of subfamily I members contained abscisic acid and methyl jasmonate response elements; however, a large number promoters of subfamily II contained gibberellin and salicylic acid response elements. HvFRF9, one of the members of subfamily II, exhibited a expression advantage in different tissues, and it was most significantly upregulated under drought stress. In-situ PCR revealed that HvFRF9 is mainly expressed in the root epidermal cells, as well as xylem and phloem of roots and leaves, indicating that HvFRF9 may be related to absorption and transportation of water and nutrients. The results of subcellular localization indicated that HvFRF9 was mainly expressed in the nuclei of tobacco epidermal cells and protoplast of arabidopsis. Further, transgenic arabidopsis plants with HvFRF9 overexpression were generated to verify the role of HvFRF9 in drought resistance. Under drought stress, leaf chlorosis and wilting, MDA and O2 - contents were significantly lower, meanwhile, fresh weight, root length, PRO content, and SOD, CAT and POD activities were significantly higher in HvFRF9-overexpressing arabidopsis plants than in wild-type plants. Therefore, overexpression of HvFRF9 could significantly enhance the drought resistance in arabidopsis. These results suggested that HvFRF9 may play a key role in drought resistance in barley by increasing the absorption and transportation of water and the activity of antioxidant enzymes. This study provided a theoretical basis for drought resistance in barley and provided new genes for drought resistance breeding.

16.
Artículo en Inglés | MEDLINE | ID: mdl-38862429

RESUMEN

DNA sequencers have become increasingly important research and diagnostic tools over the past 20 years. In this study, we developed a single-molecule desktop sequencer, GenoCare 1600 (GenoCare), which utilizes amplification-free library preparation and two-color sequencing-by-synthesis chemistry, making it more user-friendly compared with previous single-molecule sequencing platforms for clinical use. Using the GenoCare platform, we sequenced an Escherichia coli standard sample and achieved a consensus accuracy exceeding 99.99%. We also evaluated the sequencing performance of this platform in microbial mixtures and coronavirus disease 2019 (COVID-19) samples from throat swabs. Our findings indicate that the GenoCare platform allows for microbial quantitation, sensitive identification of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, and accurate detection of virus mutations, as confirmed by Sanger sequencing, demonstrating its remarkable potential in clinical application.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/virología , COVID-19/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ADN/métodos , Escherichia coli/genética , Mutación
17.
Acad Radiol ; 30(12): 2880-2893, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37225529

RESUMEN

RATIONALE AND OBJECTIVES: Bronchial arterial chemoembolization (BACE) was deemed as an effective and safe approach for advanced standard treatment-ineligible/rejected lung cancer patients. However, the therapeutic outcome of BACE varies greatly and there is no reliable prognostic tool in clinical practice. This study aimed to investigate the effectiveness of radiomics features in predicting tumor recurrence after BACE treatment in lung cancer patients. MATERIALS AND METHODS: A total of 116 patients with pathologically confirmed lung cancer who received BACE treatment were retrospectively recruited. All patients underwent contrast-enhanced CT within 2 weeks before BACE treatment and were followed up for more than 6 months. We conducted a machine learning-based characterization of each lesion on the preoperative contrast-enhanced CT images. In the training cohort, recurrence-related radiomics features were screened by least absolute shrinkage and selection operator (LASSO) regression. Three predictive radiomics signatures were built with linear discriminant analysis (LDA), support vector machine (SVM) and logistic regression (LR) algorithms, respectively. Univariate and multivariate LR analyses were performed to select the independent clinical predictors for recurrence. The radiomics signature with best predictive performance was integrated with the clinical predictors to form a combined model, which was visualized as a nomogram. The performance of the combined model was assessed by receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA). RESULTS: Nine recurrence-related radiomics features were screened out, and three radiomics signatures (RadscoreLDA, RadscoreSVM and RadscoreLR) were built based on these features. Patients were classified into the low-risk and high-risk groups based on the optimal threshold of three signatures. Progression-free survival (PFS) analysis showed that patients of low-risk group achieved longer PFS than patients of high-risk group (P < 0.05). The combined model including RadscoreLDA and independent clinical predictors (tumor size, carcinoembryonic antigen and pro-gastrin releasing peptide) achieved the best predictive performance for recurrence after BACE treatment. It yields AUCs of 0.865 and 0.867 in the training and validation cohorts, with accuracy (ACC) of 0.804 and 0.750, respectively. Calibration curves indicated that the probability of recurrence predicted by the model fits well with the actual recurrence probability. DCA showed that the radiomics nomogram was clinically useful. CONCLUSION: The radiomics and clinical predictors-based nomogram can predict tumor recurrence after BACE treatment effectively, which allowing oncologists to identify potential recurrence and enable better patient management and clinical decision-making.


Asunto(s)
Embolización Terapéutica , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/terapia , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/terapia , Estudios Retrospectivos , Algoritmos , Nomogramas
18.
Insights Imaging ; 14(1): 38, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36854872

RESUMEN

OBJECTIVES: This study compared the accuracy of predicting transarterial chemoembolization (TACE) outcomes for hepatocellular carcinoma (HCC) patients in the four different classifiers, and comprehensive models were constructed to improve predictive performance. METHODS: The subjects recruited for this study were HCC patients who had received TACE treatment from April 2016 to June 2021. All participants underwent enhanced MRI scans before and after intervention, and pertinent clinical information was collected. Registry data for the 144 patients were randomly assigned to training and test datasets. The robustness of the trained models was verified by another independent external validation set of 28 HCC patients. The following classifiers were employed in the radiomics experiment: machine learning classifiers k-nearest neighbor (KNN), support vector machine (SVM), the least absolute shrinkage and selection operator (Lasso), and deep learning classifier deep neural network (DNN). RESULTS: DNN and Lasso models were comparable in the training set, while DNN performed better in the test set and the external validation set. The CD model (Clinical & DNN merged model) achieved an AUC of 0.974 (95% CI: 0.951-0.998) in the training set, superior to other models whose AUCs varied from 0.637 to 0.943 (p < 0.05). The CD model generalized well on the test set (AUC = 0.831) and external validation set (AUC = 0.735). CONCLUSIONS: DNN model performs better than other classifiers in predicting TACE response. Integrating with clinically significant factors, the CD model may be valuable in pre-treatment counseling of HCC patients who may benefit the most from TACE intervention.

19.
Eur J Pharmacol ; 940: 175465, 2023 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-36566915

RESUMEN

Liver cancer is a kind of malignant tumor with poor sensitivity to chemotherapy. It is urgent to investigate approaches to improve the outcome of chemotherapy. KDM5A has been reported to be an oncogene in various cancers and is associated with drug resistance. However, the functions of KDM5A in chemotherapeutic sensitivity of liver cancer not been well illustrated. In this study, we found that KDM5A was upregulated in liver cancer tissue and cell lines. KDM5A knockdown using a gene interference strategy suppressed the growth of liver cancer in vitro and in vivo. CPI-455, a pharmacological inactivation of KDM5A enhanced the cytotoxicity of cisplatin (CDDP) in liver cells. CPI-455 and CDDP cotreatment resulted in apoptosis and mitochondrial dysfunction. We also found that knockdown or inactivation of KDM5A resulted in the downregulation of ROCK1, an oncogene regulating the activation of the PTEN/AKT signaling pathway. In particular, overexpression of ROCK1 or SF1670, a pharmacological inhibitor of PTEN, alleviated the cytotoxicity of CPI-455 and CDDP cotreatment. In HCCLM3 xenografts, CPI-455 and CDDP cotreatment dramatically inhibited the growth of xenograft tumor compared to CPI-455 or CDDP treatment alone. In conclusion, this study suggested that targeting the inactivation of KDM5A is an efficient strategy to enhance the chemosensitivity of liver cancer cells to CDDP by modulating the ROCK1/PTEN/AKT signaling pathway.


Asunto(s)
Neoplasias Hepáticas , Proteínas Proto-Oncogénicas c-akt , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Línea Celular Tumoral , Cisplatino/farmacología , Cisplatino/uso terapéutico , Transducción de Señal , Apoptosis , Neoplasias Hepáticas/tratamiento farmacológico , Resistencia a Antineoplásicos , Proteína 2 de Unión a Retinoblastoma/metabolismo , Quinasas Asociadas a rho/metabolismo , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo
20.
Int J Gynaecol Obstet ; 162(2): 639-650, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36728539

RESUMEN

OBJECTIVE: To develop and validate a clinicoradiomic nomogram based on sagittal T2WI images to predict placenta accreta spectrum (PAS). METHODS: Between October 2016 and April 2022, women suspected of PAS by ultrasound were enrolled. After taking into account exclusion criteria, 132 women were retrospectively included in the study. The variance threshold SelectKBest and the least absolute shrinkage and selection operator were applied to select radiomic features, which was further used to calculate the Rad-score. Multivariable logistic regression was used to screen clinical factor. RESULTS: Based on 13 radiomic features, five radiomic models were constructed. A clinical factor of intraplacental T2-hypointense bands was obtained by multivariate logistic regression. The area under the curve (AUC) value of the stochastic gradient descent (SGD) radiomic model was 0.82 in the training cohort and 0.78 in the test cohort. After adding clinical factors to the SGD radiomic model, the AUC value of the clinicoradiomic model was significantly increased from 0.82 and 0.78 to 0.84 in both the training and test cohorts. The nomogram of the clinicoradiomic model was constructed, which had good performance verified by calibration and a decision curve. CONCLUSION: The presented nomogram could be useful for predicting PAS.


Asunto(s)
Nomogramas , Placenta Accreta , Embarazo , Humanos , Femenino , Placenta Accreta/diagnóstico por imagen , Estudios Retrospectivos , Área Bajo la Curva
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